Advanced Cooling of Photovoltaic Panels Using Hybrid Nanofluids Incorporating Graphene Oxide and Carbon Nanotubes

Photovoltaic (PV) panels play a pivotal role in advancing renewable energy adoption by offering a clean and sustainable alternative to fossil fuels. However, elevated operating temperatures diminish PV cell performance, reducing energy output and accelerating material wear. This research evaluates the cooling efficiency of a PV panel equipped with a three-dimensional oscillating heat pipe (3D-OHP) integrated with hybrid nanofluids consisting of graphene oxide–copper oxide (GO–CuO), carbon nanotube–CuO (CNT–CuO), and multiwalled CNT–CuO (MWCNT–CuO). The OHP is charged with two concentrations of each nanofluid, specifically 0.1 and 0.2 g/L, to evaluate their impact on the thermal management of the PV panel. The study involved experimental tests using two PV panels: one equipped with a 3D-OHP as the cooled panel and the other as a reference panel under identical environmental conditions. Hybrid nanofluids were prepared by dispersing nanoparticles in a base fluid, and their thermal properties were characterized prior to use. Energy and exergy analyses quantify the enhancements in thermal efficiency and the reduction in entropy generation. Experimental results reveal that CNT–CuO with a concentration of 0.2 g/L remarkably improves the electrical power output by 12.07%, outperforming other studied systems with the maximum exergy efficiency of 31.2%. The findings also highlight notable gains in first-law efficiency. Furthermore, the levelized cost of energy (LCOE) and levelized cost of storage (LCOS) are analyzed, demonstrating the economic feasibility of hybrid nanofluid-based cooling for PV systems.